To Measure your dog for Coats:Measure in inches from the back of the collar, along the dogs back, to the base of the tail. The length is the size appropriate to your dog.¨(Example: 10 inches = size 10)Note: Every style will not fit every dog breed.Reversible Snowsuits - Sizes 8 to 26 - Please measure your dog and follow our sizing instructions for the best fit.